Service unavailable

What it means

The request was fine and a dependency this operation needs is not configured or not reachable — media ingest without a malware scanner, for instance. It refuses rather than proceeding, because recording an unscanned file as clean is worse than refusing the upload.

What to do

Retry later. If it persists, this is an operator problem rather than a client one; the detail names the dependency.

The response

{
  "type": "https://casanova.realty/problems/service-unavailable",
  "title": "Service unavailable",
  "status": 503,
  "detail": "A sentence about this particular occurrence.",
  "instance": "/api/v1/properties/some-listing"
}

Content type is application/problem+json. Match on type, not on title — the title is prose and may be rewritten.